The present invention relates to the mining of mineral deposits, in particular coal mining.
While various different types of mining procedures have been used over the years for the mining of coal, these procedures basically fall into two categories, underground mining and strip mining. In underground mining, there are several different types of procedures including room and pillar mining, long wall mining and hydraulic mining. In all of these procedures, however, tunnels in the earth are made through which the miners enter the earth to the location of the coal for carrying out the mining operation. In long wall and hydraulic mining operations the roof of the tunnel must be supported by leaving pillars in the seams. The pillars can reduce recovery by as much as 50%.
In strip mining, huge areas of the earth must be removed in order to extract coal from along the coal seam. The area of the earth over which the strip mine extends depends upon the depth to which the coal seam is to be mined. The deeper the mining of the seam the wider the area of the earth that must be disturbed.
Various attempts have also been made at conducting drilling operations between various tunnels underground; exemplary of such attempts are the embodiments illustrated in U.S. Pat. Nos. 3,167,354 and 4,123,109. In addition, some attempts have been made at subterranean hydraulic mining of mineral deposits such as shown in U.S. Pat. Nos. 3,874,733 and 4,092,045. Furthermore, with respect to the process of mixing the mineral deposits, such as coal, in a slurry for the purposes of transportation along a pipeline, such techniques are shown in U.S. Pat. Nos. 3,041,053 and 3,924,895.
With the increasing necessity for economically and efficiently obtaining sources of energy, it has become even more critical for finding new techniques for the mining of coal. Such problems are especially enhanced in light of the safety considerations in tunnel mining and the environmental concerns with strip mining.